1. Field of the Invention
The present invention relates generally to variable electrical resistors and, more specifically, to an improved variable resistor that minimizes noise and wear resulting from use.
2. Description of Related Art
Conventional variable resistors have utilized a sliding element resembling a brush. The sliding element slides across a surface of a resistor element and a conductive element to vary resistance. However, noise is generated as a result of the brush element lifting from the resistor element as it slides across the resistor element and the conductive element. Obviously, noise generation becomes more of a problem as the requirement for steady resistance increases. There is the additional problem of not achieving a smooth motion by the sliding element, which also adversely affects the degree to which the variance can be controlled. The lack of smooth motion results from the large amount of friction between the sliding element and the resistor element, as well as the conductive element.
Another problem has been performance deterioration. This results from frictional wear constantly caused by the sliding element sliding across the resistor element and the conductive element each time the resistance is changed.
A need still exists in the art to provide an improved sliding type variable resistor which minimizes wear and noise.